This will allow improvements to the pmaps so that they can more easily defer expensive operations, eg tlb/cache flush, til the last possible moment.
Currently this is a no-op on most platforms, so they should see no difference.
Reviewed by Jason.
This is a completely rewritten scsipi_xfer execution engine, and the
associated changes to HBA drivers. Overview of changes & features:
- All xfers are queued in the mid-layer, rather than doing so in an
ad-hoc fashion in individual adapter drivers.
- Adapter/channel resource management in the mid-layer, avoids even trying
to start running an xfer if the adapter/channel doesn't have the resources.
- Better communication between the mid-layer and the adapters.
- Asynchronous event notification mechanism from adapter to mid-layer and
peripherals.
- Better peripheral queue management: freeze/thaw, sorted requeueing during
recovery, etc.
- Clean separation of peripherals, adapters, and adapter channels (no more
scsipi_link).
- Kernel thread for each scsipi_channel makes error recovery much easier
(no more dealing with interrupt context when recovering from an error).
- Mid-layer support for tagged queueing: commands can have the tag type
set explicitly, tag IDs are allocated in the mid-layer (thus eliminating
the need to use buggy tag ID allocation schemes in many adapter drivers).
- support for QUEUE FULL and CHECK CONDITION status in mid-layer; the command
will be requeued, or a REQUEST SENSE will be sent as appropriate.
Just before the merge syssrc has been tagged with thorpej_scsipi_beforemerge
- pmap_enter()
- pmap_remove()
- pmap_protect()
- pmap_kenter_pa()
- pmap_kremove()
as described in pmap(9).
These calls are relatively conservative. It may be possible to
optimize these a little more.
This adds support for EtherExpress/16 cards with 16k of RAM, and in the
process adds general support for PIO mode on these cards. This entails
changing the way the i82586 driver handles bus barriers, since it doesn't
allow for strange cases like this.
This has been tested on the i386 port with the 'ix' driver in both
16KB (which was the source of the problem) and 32KB modes, as well
as with the 'ef' driver. I've tested it (briefly) with 'ei' on arm26
as well. In theory, drivers other than 'ix' should follow precisely the
same code paths as before.
the stack, and remove the no-longer-necessary PHOLD()/PRELE() calls
in fdformat().
(This eliminates 1/3 of the instances of PHOLD()/PRELE() in the kernel code.)
XXX We still have too many mostly-redundant floppy drivers.
Only the low nibble is defined, and on at least one 3gx (mine) there is an
undefined bit which reads as a one -- bit 6 (0x40). This screwed tctrl_intr()
which would loop forever, thinking it always had new events to process.
* Disable the DMA engine when setting up a DMA transfer, just in case
the 5380 driver didn't instruct us to do so already.
* More useful debug output when entering the "left-over bytes" case after
a DMA transfer finishes.
transfer count being smaller than the minimum transfer size for which
we would use DMA. The device may be disconnecting, to complete the
transaction at a later time. Just let the 5380 engine proceed acting
on the current SCSI bus phase.
"off_t" and the return value is a "paddr_t" to allow mappings
at offsets past 2^31 bytes. Somewhat inspired by FreeBSD, which
only changed the offset to a "vm_offset_t".
Includes updates for the i386, pc532 and sh3 mmmmap from Jason Thorpe.
